Proximity and direction indicator



De- 28, 194s,

F. E.' BEs-r PROXIMITY 'AND DIRECTION INDICATOR y Filed Jnf 9. `1942 Paws: Jal/ Patented Dec. 28, 1948 UNITED STATES -()ITFICIEI QPRQXIMITY. AND "-DIREUTIN `INDIKCATOR .TF1-ank EllisonBest, Indianaimlialnd.

Application 'January 9, 194 g,.S.erialNn. 42.6.19.0

" 'This invention relates'to agproximity and direction indicator for use on aircraft,r Watercraft or land vehicles to aid in the prevention` of colli- Serial No. 407,087, le'ci August '1941. .now

abandoned.

It 'is an object of.`tl1`is invention to ,provide proximity and direction 'indicator means of simple andefflcient construction adapted yto 'be installed ona number of movingbo'dies such asa '.groupof aircraft, watercraft, .land vehicles, etc., 'and .operable to' broadcast "from each moving' bo'dy soequipped a radio signal for reception by all other nearby moving bodiessimilarly equipped to provide information on eachmovingbody as to the proximity and direction .of .each .other nearby moving body ,of the -group.

It is another object of thisinven'tion .to provide means for .continuously .transmittingfrom a station, such .as .from .a moving body, a .frequently interrupted .radio signal ,of .predetermined frequency, and means for receiving. atthesame station, during time increments whenlthe .transmitting from that station iis interrupted. signals of the same frequency'thatare broadcast :from other nearby stations, thereby providing for both 'continuous intermittent transmission and continuous intermittent reception'fromlthe Same station on the same .frequency vwithout.interference between they said transmission and reception.k

-It sometlmeshappens that two-.aircraftwill ocllide in flight, usually with fatal results .to the `pilot-sand passengers and complete .destruction of both of the colliding craft. "Such accidents vmay be due to'carelessness'but are more'liable .to

be `due'mthefact that the pilot of neither craft could seethe othercraft untilit was 'toolateto prevent the collision. lPoor visibility can occur `in dense fog .or clouds oratnight orit can bedue 'to blindspots inherent inthe construction .of 'the aircraft. Such accidents -can also .occuriniblind flying, i. e., when the pilots are "flying entirely equipped with this `proximity and direction indi- `-'ca'tor and to'require them to continuously broad'- cast a signal While innight and to continuously maintain their receiving apparatus open for the 2 reception fof -the signals from :all Yother aircraft 'While lin lllghtso -thatthe pilotof #each aircraft Linfight -would always `receive a signai'fromevery 'other Inearby aircraft `in t'flight indicating the proximity and direction of the other aircraft in `ampletime to-enablefthe-pilot to-avoid-a collision.

As applied to aircraft to aid in maintaining desired `formations iin flight and landing, each 1aircraft of thegrouporlsquadron'is equipped with 'one of Itiresedevices Aand receives a signal from every other aircraft ein the -group `showing veach pilot theproximity :and location Yof every other aircraft =in fthe group. This makes -it possible izo-maintain' correct''formationsinrig'ht and landing-underall conditions-of visibilitysuch as when flying through clouds or fog'orat night, vor when 'flying blind,i.-e.,byfthe use of instruments only.

As applied'tofaircraft Vfor military use for detecting rWhether anotheraircraft `in the vicinity is a friend -or foe, this Ydevice is installed on all oi the `aircraft 'used fby 2one group in the 'conflict "andthepilotffo each craftso equipped would be abletoiidentify and1tell the location-of al friendly `craft by Fthe #signal lreceived therefrom and -to Videntify ahostlle craft bythe absence'of any such s'ignaltherefrom.

l lofaccidents,ftheddentiflcation'of friend and foe in-battla and the maintenance'of vdesired forniaytions -under all conditions of visibility.

-Other-objects ofthe invention willbe apparent from the following description taken in connecntion with'the accompanying drawings.

In yfthe drawings Figure A1 "is 'a `diagrarnmatic 'view `of `the radio receiving and amplifying means 'and 'the signal 4means -of a'proxi'mity and-'direction indicator constructedin accordance with my yinvention showingparts of the same in cross section.

Pig. Elsa' detached'isometric'viewof an interrupter -adapted `te be 4used in 'the Jtransmitting and receiving'eircuits-of my-device.

Figu is ajdiagrammatic'yiew of a transmitter -embodiedin' thisdevice.

Fig. 4iisaf1agmentary sectional view showing directional Preceivingfmeans. `of 'modified form.

Like-reference numerals designate like parts throughout the'several views.

:The A,radio transmitting devices, shown dia- .'grarnnniticallyv inlFig. `3, Acomprise a conventional radio transmitter Ivlil, capable `of producing and transmitting, through -an rantenna Il, a .radio 3 or electromagnetic wave, suitable for signaling purposes and preferably on a frequency that is not ordinarily used in long and short wave broadcasting and radio beams to thereby avoid confusion with ordinary broadcasts. The transmitter I is connected by conductors I2 with a source of power I3. An interrupter I4, shown diagramnatically in Fig. 3, and more in detail in Fig. 2, is connected in series with the transmitter I0.

The radio-receiving and signal devices are shown diagrammatically in Fig. 1. The directional radio-receiving antenna means includes a body such as a sphere I5 formed of material, such as lead, which will shield or deflect radio Waves. Obviously this body I5 could be a g'ureor. frame or body of different shape.

A plurality of radio receiving"'antenna loops,

Each directional radio receiving loop on the body I5 is connected with a radio amplifying device. For instance, the eight directional radio receiving loops I6 to 23 inclusive, shown in Fig 1, are respectively connected by conductors 26 with radio amplifiers Ito 8 inclusive. ergy from an outside source isvsupplied tothe radio amplifiers I to 8 through conductors 21 connected therewith. Obviously the conductors 21' may be connected with the power source I3.

The visual signal device shown vherein comv-l prises a semi-spherical body member 28 carrying signal lights arranged in pairs and disposed so that the position of each .pair of signal lights corresponds to the position of two diametrically opposite radio receiving loops on the body I5. Eight signal lamps are shown in Fig, 1 and are numbered 3|) to 3 1 inclusive. Preferably the two lamps of each pair are of different colors, such, for instance, as red and green. In Fig. l it is Electrical en'- 'animes assumed that the lamps 30, 32, 34 and 36 are.l

green and the lamps 3|, 33, 35 and 31 -are red. Obviously this color arrangement may be varied or the lamps may all be of the same 'color and other means or markings used todistinguish between them. v

Where green and red lamps are used, as above described, the lighting of a green lamp could indicate the presence of another moving body to the rear of the one 1receivingvthe signal and the lighting of a red lampjcould indicate the presence of another moving body in front of the. one receiving the signal.

In some instances a plurality of adjacent lights may be lighted-,simultaneously by signals coming from various angles as respects the planes of the energized loops thereof. `Thus in some instances more than one red light or morethan one green light may be lighted and the position of the transmitting device that is actuatingthe lights may be determined partly .by the .brightness orintensity of the lights ,thusl differently energized The green lamps 30, .32, 34 and 36 are respectively connected by conductors 38.with the radio amplifiers 3, 4, 5 and 6,'whicnamp1iers 3, 4, 5 and 6 vare connected respectively Withthe radio-k receiving loops I8, I5, 20 andy 2l by the conductors v 26. This connects the green lamps with the .loopsl I8, I9, 2l) and 2| that are on the side of the body I5 toward the rear of the aircraft or moving body. Thus the lighting of a green lamp indicates the presence of another craft generally to the rear of the receiving craft.

The red lamps 3l, 33, 35 and 31 are respectively connected by conductors 39 with the amplifiers y1, 8, I and 2 and said amplifiers 1, 8, I and 2 are respectively connected with the vloops 22, 23, I6 and I1. This connects the red lamps with the loops 22, 23, I6 and I1 that are positioned on the side of the body I5 toward the front of the craft. Thus the lighting of a red lamp indicates the l presence of another craft generally in front of the receiving craft.

The position, on the member 28, of the lamp or lamps that are lighted indicates whether the other craft is substantially in line with the re- `ceiving craft or is above or below or to one side vor the other of thereceiving craft.

The 'body I5, being a, radio shield, will prevent anyv and all loops that are shielded or blocked v4the amplifier by which it is controlled is `corn.-

pleted through the frame of the member 28, along conductor 40 `through an interrupter 4I, shown diagrammatically in Fig. 1, and more in detail in Fig. 2 and along conductors 42 to the several amplifiers I to 8.

The interrupters I4 and 4I, illustrated diagrammatically in Figs, 1 and 3, are preferably embodied in one unit, as shown in Fig. 2, and are in the form of discs rigidly mounted on a com- Imon shaft 43 and constantly driven by any suit- '.with'the electrically conductive sections 44 of the `other disc. member and each insulation section 45`is of substantially equal width to the electrically conductive section 44 with which it registers. The width of the sections 44 and 45 circumf ferentially considered is variable,` some beingwide and some being'narrow.

Obvicuslythe arrangement and relative positioning of these'ctions 44 .and 45 of the two interrupter 'discs I4 and 4I can be varied so long as..

the said sections 44 and 45 are paired so that when the discs I4 and 4I are rotated the circuits controlled thereby will be alternately and rapidly l opened and closed, lone of said circuits always being open whenI the other is closed.

The disc member I4 is the interrupter in the transmitter y circuit and the disc member 4| is the interrupter in the circuits `of the receiver and visual signal mechanism. Two relatively insulated brushes 46 and 41 are positioned in brushing ,contact with the peripheral portions of therespective disc members I4 and 4I and are connected with suitable conductors in the transmita *ting and receiving 'circuits respectively so that *they will control the owo'f current lin :these cir- "cuits,

'Obviously the lnterrupterarrangement @just described will lprovide 'an interrupted Acurrent `in fboth *the transmitting `circuit (and `the receiving and signaling 'circuit so that 'the transmitter and receiver will rbe 'operated alternately and each will bein operationoone halfofthe timebutithe transmitter and 'receiver circuits 'will never both Ibe 'in operation lat the same time. I'[*his makes lit J:impossible Afor 'a 'receiver at 'one 'station tto be 'operated 'by the transmitter at the same station.

vPreferably 'a 4switch 'lis provided in the circuit of the interrupter 4I.

In addition `to `the visual signalling means ihcreinbefore describedzandzpreferably electrically connected in parallel with said :herein'before described visual Lsignalling means .I .preferably provide another signalling means that may be used in conilunction with saidvisual signalling imeans and that iis lcapable -of operating independently in y-icasiersaii 'visual signalling means fails .to operate l01' iisout-'o orden-or ^is turned This second fsignllingmeans may be eithervisible or audible, and one that will operatesatisfactorily comprises :an -au'dile signal device, such as La horn 49, fand "an interruptor A|) connected .in .series 4'with the amplifiers i .to .inclusive iby conductors F54 in :such `a manner lthat of the ampli- )hers EI to B .is .actuated by the .energizing 4.of one of 'the radio receiving loops the Lhorn 49 -will "be souned. This will .call .the :attention of the pilot to the .fact that .there 'is another moving craft .in ltlxe vicinity and tofobserve .th'evisual signal to ascentainftheilocationof `the other craft.

Preferably a switch '5`I is provided in the circuit 'o the horn 49 so that `this auxiliarysignal tmay fbe used or -shut off .at lwill.

"Ihe interrupter -50 'lis `preferably another disc like the disc `4I :secured lto the shaft 43 and synchronlzed with the transmitting disc I4 in the vsaine marmer `as the disc 4fI., tosupp'ly current to the horn "43 only 'in *the 'increments of 'time .when 'the transmitter circuit is inoperative.

In Fig. 4 I show a body 52 of radio shielding'm'aterial which corresponds to the body I5 except that it is shaped to provide cups 53 wherein directional radio-receiving loops I6 to 23 are positloned. The cups 53 may vary in depth depending on the extent of shielding desired. This cupped structure makes it possible to more effectively shut off the incoming signals from radio-receiving loop members that are not positioned substantially parallel in line with the direction of the received signal and renders the device more accurate and more selective.

Obviously part of the body l5 with part of` the loops thereon and a corresponding number of amplilers and signal lamps may be used. For instance, if no information relative to aircraft to the rear of the receiving craft is desired then only the front portion of the body I5 With the loops thereon would need to be used with one amplier and one lamp for each loop.

Also a group of the directional radio receiving loops may be supported in substantially semispherical relation or at various diierent angles on a frame or body that does not form a radio shield. In this event each loop will be actuated by a signal coming from either of two directions substantially parallel in line with the direction of the received signal. When this is done the number of signal lights can be correspondingly re- 1ences and ughts tci -uirferent colors are not required. l

`=In the'useofthisiinvention onair -water and/or land' craft -each -craf-t of a kgroup will fbe equipped vvitrroneoithesedevicesiincludinglboth"clneltransh rmitting and the receiving and signaling tapparatus lIn eachinstallationf'the body I5 and light support 28 are both rigidly-mounted in the 'craft 'in the proper lpositions relative 'toveachotherand suitable means are kprovided ffor supp-lyingfele'ctric current to the apparatus and for driving Jtheinterrupters F4, II 'and 5I) fat vall 'times `when vb'the vcrait is -in motion. 'This Ybroadcasts 'from feach 'craftgwiiilein motion, an interrupted radio wave `of ka known A'frequency preferably distinctive from the `'frequenc'ies*of radio broadcasts, radio beams, and like :disturbances to which v`the `crait 4will ordinarily ybe subjected.

At the same time the receiving fapparatus :of leach Acra'i't is continuously 'operating sand ready to receive "an :incoming lsignal so that when 'two Vor more craft equipped :With these @devices :ap-

proach-eachother the lreceiving apparatus fofseach craft will lpick up the broadcasts trom the :other craft fand lwarn fea'dh Vpilot "of 'the proximity :and locati'ons of -theotlrercraft 'll'iiswarning Iwill fbeconveyed to Jea'cl'i pilot :both fas fan `audible :and a visual signal and the visual signal Iwill appraisethe pilot of the location of theiotherfcraftrelative to 'his fown. 'The brightness fof 'thersignal :light or 'lights wllindicate fthe distance .of'fthe other craft land the order :in which vvsuccessive ylights lare lighted and lextinguished and chan-ges fin abr-ight- -n'ess of the lights :will indicat'e the .direction `rof travel .of the Tdth'er :craft and 'whether it is eapvpreaching lor .receding .Troni the receiving craft.

fFor dnstance, :if :a fsignal Vthat is broadcast 'from the vvtransmitter :in Fig. .is picked up by .the loop 1I 9 'of filig. :1, it Nvill factuate @or zcontrolithe radio. fa'mplifler 4 Vin lsuc'h .a Lmanner Vas to cause vsaid amplifier x'4 V.to *enough current 'to fthe green lamp &2 tolightsaidlamp thus indicating 'to the pilot inf :the .receiving :craft vthat 'there Yis `another icraft fbehind :him 'fand tto his right.

It will be noted that the alternate sectionstof electrically Yconductive imaterial -44zand insulating materiali on the interrupterfdiscs Ilianrl rMaarre of different Width considered circumferentially of these discs.

Also these discs may be rotated at different speeds in the different signal units. This makes it impossible for the insulating sections 45 of a disc 4I in the receiving circuit of one signal unit to operate in exact step or synchronism with the insulating sections 45 of a disc I4 in the transmitting circuit of another signal unit and thus completely blank out and fail to pick up a signal.

From the foregoing description it will be seen that this proximity and direction indicator can be used on moving bodies in air, in or on water, and on land to transmit signals between those bodies for many different purposes, such as for the prevention of collisions, for indicating whether another moving body or craft is the craft of a friend or foe and for showing to each pilot and/or driver on a moving body the relative position of the other moving bodies of a group to thereby help him maintain a desired formation under any condition of visibility.

Obviously the signals transmitted by my device may be broadcast in code and may be de-coded in the receiver before they actuate the signal devices. Coding apparatus suitable for this type of code broadcasting and receiving is disclosed aww@ confusingly similar broadcast and thus renier 5 the signalling system useless or yturn* it vto his own advantage, such asjto represent himself as .a friend instead of foe.

Obviously changes in `this invention may be made uwithin the scope and spirit of the follow- `l0 ing claims.

`Having described my invention, what Ieclaim as new and desire to protect by Letters Patent is:

1. In aproximity and direction indicator, 1rotatable electric circuit interrupter means, coni- .15 e prising two relatively .xed circular rows ofi alternate conductor and insulator"members,v each conductor of each row' being paired .with sulator of equal width oi. v.the -other Tow, two

oontactors positioned for simultaneous:engage-,20.I

ment with the conductorand insulatortmember i' of each pair and for successiveeu'gag'enient 'with f, said pairs of conductor and? insulatorflmenibe'rs I as the circuit interrupter vis'rotated,v a. transmitterpcircuit 'connectedwith yone of said'- con-|25 e testers, a lreceiving 'circuit connected vWith-'the other of said contactorsvand signal devices-and said receiving circuit.

2. In a proximity and directionrv indicator,,30v rotatable electric circuit interrupter means,` coml prising two relatively xed circular rows 0f alternate conductor and insulator members of variable 1 Widths, each conductor of each row being paired.

with an insulator of equal width of the otherj5Y row, two contactors positioned for simultaneous engagement with the conductor and insulator j i member of each pair and for successive engagement with said pairs of conductor and insulator members as said circuit interruptler is rotated,i,49

a transmitting circuit connected with .one oisaid contactors, a` receiving circuit. connected. with the other of said contactors and signal devices and direction #distinguishing means (connected g 45 with saidgreceiver means( i 3. A proximity and direction indicator` .com-

.mivwsln prising rotatable electric circuit interrupter i. e i

means having two .relatively fixed circular rows of alternate conductor and insulator members of variable widths, each conductor of each row being paired with an insulator of equal widtn of the other row, two contactors positioned for simultaneous engagement `with each conductor and insulator member of each pair as the circuit yinterrupter i-s rotated, a transmitter circuit controlled by onerow of conductor and insulator members, a receiver circuit controlled by the other row of conductor and insulator members, and signal. devices and direction distinguishing means connected with said receiving circuit.

` FRANK ELLISON BEST.

.ille .of .this patent:

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